Dr. Johanna Rubba
English Department (Linguistics)
Cal Poly State University San Luis Obispo
Last updated 11/3/11
© 2011 Johanna Rubba
Syntax: Terms and Concepts
Clauses and Their Elements

Constituents: To understand syntax (for English or any other language), it is crucial to understand the concept of constituents. A constituent, simply defined, is a building block of syntactic structure, whether at the level of the phrase, clause, or sentence. Constituents play roles or fulfill functions in syntactic structures. Some roles most people have heard of are subject and direct object.

Our subconscious knowledge of our native language's syntax consists of a set of patterns made up of various constituent roles. But these patterns aren't "filled in"; they are strings of slots or blanks labeled with the constituent roles. When we make a sentence, we choose a pattern and assign particular words and phrases to the roles. We do this extraordinarily rapidly and, most of the time, are not aware of any effort in doing so.

It is very important not to confuse a constituent role with the kind of syntactic element that fulfills the role. In most cases, more than one kind of element can play a constituent role. A role that is manifested by a variety of different kinds of expression is adverbial (not to be confused with adverb, which is a word class). One kind of adverbial modifies the verb in a predicate, giving information about time, place, purpose, and manner. This variety of meanings permits a variety of structures to occupy an adverbial role. In the following sentences, the underlined portions all play the role of adverbial.

We will ski  at Mammoth  this winter.   At Mammoth: prepositional phrase, adverbial of place    This winter: noun phrase, adverbial of time
We will ski expertly.   Expertly: Adverb, adverbial of manner

We will ski after Fall semester has ended.  After Fall semester has ended: subordinate clause, adverbial of time.
We will ski because it's our favorite sport
Because it's our favorite sport: subordinate clause, adverbial of purpose

There is a somewhat unfortunate tradition in linguistics to use the term phrase interchangeably with constituent. This is misleading, because, outside of linguistics, a phrase is understood to contain more than one word. A single word can be a constituent, however; consider a sentence like Cats are lazy. Cats is a single word, and it is also a constituent: subject of the clause. Teachers of introductory syntax are always faced with explaining to students how a single word can be a phrase. To avoid this confusion, in my own work I use phrase to mean a group of words most of the time and constituent to mean constituent.

The remainder of this section defines clauses and the major clause roles, and moves on to describe major predicate roles.

: a unit of syntax consisting of at least two constituents, a subject and a predicate. Clauses are the building blocks of sentences, although they can also be constituents of phrases (see the discussion below). The usual structure of clauses in English is subject + predicate. The subject is the topic of discussion that the particular sentence focuses on -- this is very often a topic or subtopic of the text in which the clause appears.
The fact that the predicate gives information about the subject is the grounds for the overly vague traditional definition of subject, the subject of the sentence is what the sentence is about. It is far more informative to say that the subject is what the predicate tells us something about. This, of course, requires that we have some means of determining what is the subject and what is the predicate of a sentence. For a technique native speakers of English can use to do these, go to the page "Finding Subjects."

Consider this little text, which consists of three clauses:

My mother works for IBM. She is the personnel manager at their San Jose facility.
Her office has its own bathroom.  

The general topic of this text, the main person or thing under discussion, is 'my mother'. An expression referring to her -- 'my mother' in the first clause, 'she' in the second -- is the subject of the first two clauses. Notice how the rest of each clause -- the predicate -- gives a comment: some information about the topic. The predicate of the first clause tells where she works; the predicate of the second tells what her position is. The third clause has a different, but related subject: we know from our knowledge of the world that a manager in a major company is likely to have an office of her own. So a subtopic, 'her office,' occurs as subject in the third clause. Notice that the predicate of that third clause, has its own bathroom, gives a comment about the office.

As is frequently the case for expository texts like this, the subject position in each sentence is reserved for something topical: it is used to introduce a topic or subtopic the first time it is mentioned (as in the first and third sentences), and it is used to retain an introduced topic for further comment, as in the second sentence. In this way, subject position serves as a tool for text cohesion by relating incoming new information to the current focused topic of the text.

Our definition of subject is different from another one offered by traditional grammar: the subject is the clause element which performs the action of the verb. This is a typical definition for subject, but it is only accurate in certain types of clauses. Not all clauses involve action; and sometimes the topic of our conversation is not the performer of the verb's action. For example:

a. Carlos resembles his grandfather.
b. Two students were injured at the football game last night.
c. Oversleeping yesterday saved my life. My carpool mates had a terrible crash.

Sentence a. does not involve any action: Carlos isn't 'doing' anything; he just possesses certain physical traits. In sentence b, there is action -- injuries happen -- but the sentence is about the people who suffered the injury, not the thing that caused the injury. The cause of the injury isn't even mentioned in the sentence. In sentence c., there is also no action in the verb 'save': it refers to a situation rather than an action.

Clause elements (building blocks of clause structure)

Functions of consituents within clauses

These terms name functions or roles played by syntactic units inside a clause. The units which can play these roles may be clauses as well as non-clause constituents.

Subject - a topic of discussion, about which the predicate makes a comment. May be a nounn phrase or a subordinate clause (or other type of unit in certain sentence types). Except when the subject position introduces a topic, the subject is usually given information, that is, information that is already known to all the particpants in the communication.

Predicate - makes a comment about the subject. Will always include a verb, although the verb may or may not carry a present- or past-tense marker (see finite/nonfinite, below). The predicate may contain additional elements that modify the verb or subject: NPs, PPs, APs, AdvPs, or subordinate clauses. New information is usually contained in the predicate, especially in the last position. Most predicates contain some given and some new information (new information is information that only the speaker knows, and wishes to communicate to the other people involved in the communication event.)

Sentence-level adverbial - This is an adverbial that makes a comment on the whole sentence, not just a part of it. It is often an evaluative comment. One characteristic of sentence-level adverbials is that they can move around. They may be placed at the beginning, middle, or end of a sentence. In the following examples, the sentence adverbial is in italics.

Unfortunately, your mother's condition has worsened.
sentence adverbial sentence

Your mother's condition, unfortunately, has worsened.
Your mother's condition has unfortunately worsened.
Your mother's condition has worsened, unfortunately.

Obviously, your friend doesn't really want to come to your party.
sentence adverbial sentence

Your friend obviously doesn't really want to come to your party.
Your friend doesn't really want to come to your party, obviously.

Sentences with sentence-level adverbials can often be paraphrased with the adjective version of the adverb, thus:

It is unfortunate that your mother's condition has worsened.
It is obvious that your friend doesn't really want to come to your party.

Or thus:

That your mother's condition has worsened is unfortunate.
That your friend doesn't really want to come to your party is obvious.

Sentences with adverbials within the predicate cannot be paraphrased in these ways:

He carefully inserted the key into the lock. 'Carefully' is in the predicate, modifying the verb, not the whole sentence. (* means that a native speaker would reject the sentence.)

* It was careful that he inserted the key into the lock.
* That he inserted the key into the lock was careful.

Predicate Roles

A sentence describes an event, a scene, or a situation. These scenarios may involve people, objects, times, places, reasons, etc., etc. Linguists often refer to the people and objects in a scenario as participants, even if they aren't doing anything in particular.

Constituent roles express aspects of a scenario; they are very much based on the real relations and events the speaker is talking about.

When we create an utterance to express information about a scenario, we make many choices: What words will we use? What sentence patterns will we choose? How will we assign participants in the scenario to constituent roles? How do we do all this in a way that helps our listeners or readers follow our meaning easily? We make these choices incredibly rapidly, and, again, usually not thinking about it. Most speakers of most languages could not explain the choices they make if their lives depended on it; it takes extensive training in grammar, semantics, and discourse to do so.

Usually, a great deal of information the speaker wants to express resides in the predicate. A number of roles are found there.

Direct object - this is present in a clause that portrays an action or event with two or more participants, in which at least two participants are named. The direct object is the person or thing that the action of the verb is directed towards. A direct object may be a NP or a subordinate clause. The direct object can be thought of as an undergoer of the verb's action in many cases.

I ate a large pizza.
(names participant #1: doer of eating action) action (names participant #2: undergoer of eating action [the pizza got eaten])
subject direct object

The pilot saw a UFO.
(names participant #1: doer of seeing) (names participant #2:
undergoer of seeing [the UFO was seen])
subject direct object

Indirect object - this is present in a sentence that portrays a three-way action or event: there are at least three participants. The indirect object is the expression that names the participant who benefits from the action, or who receives the direct object, or who is indirectly affected by the verb's action. An indirect object may be a NP or a subordinate clause. Thinking of the events in order may help sort out direct from indirect object: First, the agent found the job; then, I got the job. First, Susan sent the birthday card, then, her girlfriend received it. This is helpful especially because the sentence order has the indirect object first.

My agent found me a job.
names participant #1:
did the finding
action  names participant #3: benefitted from the action (got the job) names participant #2:
is the thing that was found
subject verb INDIRECT OBJECT direct object

The Mustangs gave the Grizzlies a serious beating.
names participant #1:
did the giving
action names participant #3:
got the beating
names participant #2:
what was given
subject verb INDIRECT OBJECT direct object

Susan sent her girlfriend a birthday card.
names participant #1:
did the sending
action action names participant #3: got the card names participant #2:
was sent
subject verb INDIRECT OBJECT direct object

My husband made  the baby some mashed carrots.
names participant #1:
did the making
action names participant #3:
got the carrots
names participant #2:
were made
subject verb INDIRECT OBJECT direct object

There is a failsafe test for indirect objects: if you can express the same role with a PP using 'to' or 'for' placed after the direct object, you have an indirect object. I call this the 'to-for test'. Examples:

My agent found a job for me.
The Mustangs gave a serious beating to the Grizzlies.
Susan sent a letter to her girlfriend.
My husband made some mashed carrots for the baby.

Subject complement - this is an expression that occurs after the verb, but describes the subject of the sentence. The meaning of the subject complement is tied to the subject. In traditional grammar, these are called predicate nominatives when they are NPs and predicate adjectives when they are APs.

My father was a dentist.
subject describes my father
subject complement 
(predicate nominative)

The horses are very beautiful.
subject describes the horses
subject complement
(predicate adjective)

Object complement - This also occurs after the verb, but it describes the direct object. (Sentences with subject complements do not have direct objects.)

We consider her the best candidate for the job.
subject direct object describes 'her'
(object complement)

found the new guy very handsome
subject direct object describes 'the new guy'
(object complement)


Adverbial - Provides descriptive information about the verb's action. Phrases or clauses can be adverbials; the phrases can be PPs (not all adverbials are adverbs!!) or AdvPs. Adverbials answer questions like when, why, in what manner, in what way or fashion, how, where. It is not uncommon to have several adverbials in a sentence, giving various types of information.

We crushed grapes in the wooden tub.
subject direct object adverbial
(tells where the 
crushing took place)

We  stomped on the grapes fiercely.
subject adverbial
(tells where we 
(tells how we stomped)

Kinds of clauses: Finite and nonfinite

Finite: 'Finite' in grammar means 'tied to a particular time that is known in relationship to the moment of speaking or writing'. A finite clause has a tense marker in it: a main verb or helping verb that indicates, through a suffix or through its form, the time at which the event, action, or state took place. When you hear a finite clause, you can tell whether the event described by the clause happened before the moment the clause is said (past), or is true at the moment the clause is said (present) or is going to happen after the clause is said (future).


Marla has written her essay for the grad school application.

Has written tells us that the action took place before the clause was spoken/written.

Americans vote for President every four years on the first Tuesday in November.

The form of the verb vote tells us that this statement is true at the time the clause was spoken/written.

The redwoods will be clearcut starting tomorrow.

Will be clearcut tells us that the event has not happened yet.

I would have called him this morning, but my cellphone is on the fritz.

The presence of have after would and the'-ed' ending on call tell us that this is a hypothetical statement about the past. If we change it to would call , we understand that it is a hypothetical statement about the present or future.

Notice that tense sometimes is shown by the main verb if it is alone ( as with vote), and sometimes by a helping verb (an auxiliary verb) such as has in has written and will in will be clearcut.

Nonfinite: If finite means 'tied to a particular time that is known in relationship to the moment of speaking or writing', then nonfinite must be its opposite: 'NOT tied to a particular time that is known in relationship to the moment of speaking or writing'. A nonfinite clause has a subject and a predicate, but no tense indicator: we may be able to tell whether a process or finished act is talked about, but we can't necessarily tell when it took place. Nonfinite clauses play the same roles as constituents in sentences: they can be subject, adverbial, direct object, etc.


a. I see Mary eating strawberries.

b. I saw Mary eating strawberries.

c. I will see Mary eating strawberries.

Mary eating strawberries has the structure of a clause: a subject (Mary), and a predicate consisting of a verb + direct object (eating strawberries), which gives some detail about Mary. Yet nothing in this clause ties it to a particular moment in time. Sentence a. puts the event of strawberry-eating in the present; sentence b. puts it in the past, and sentence c. puts it in the future. The placement in time of the strawberry-eating event is indicated by something else in the sentence: the form of the verb see. The nonfinite clause Mary eating strawberries appears inside of another clause in all three sentences, a., b., and c. For instance, the structure of a. is:

[ I see  [Mary eating strawberries] ].

I see Mary eating strawberries. The subject is I, and the predicate is see Mary eating strawberries. Mary eating strawberries is the direct object of see, just as your brother is direct object in a sentence like I see your brother over there in the parking lot.

Notice, too, that Mary eating strawberries can't be a sentence by itself in formal English, e.g. *Mary eating strawberries by the pool. In informal English, this might be said alone as an answer to a question (e.g., What do you see?), but in formal writing it would be considered a fragment.

The following sentences are similar:

a. We heard the tree fall / the tree falling.

b. I hear the tree falling.

c. The loggers are at work -- in five minutes you will hear the tree falling / the tree fall.

Notice that if the nonfinite clause were to stand alone as a sentence, we would need a tense marker in the clause, on the verb or on a helping verb: The tree falls; the tree fell, the tree is falling.

Independent (main) and dependent (subordinate) clauses are discussed in the section on sentences.

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